The invention relates to a hair-shaping appliance, in particular steam styling tongs, having a tubular drum which treats the hair and is provided with through-passages, having a heating device, in particular for heating up the drum, having a dosing device, upon the actuation of which liquid passes out of an outlet of a liquid container via a liquid-channeling device, having an evaporating device which is supplied with heat by the heating device and evaporates liquid into steam, and having a steam-distributor chamber which adjoins the evaporating device and via the through-passages of which steam flows outward.
DE-C-26 31 798, for example, discloses an apparatus for the metered discharge of liquid for a hair-shaping appliance, for example steam curling tongs. For the discharge of the steam, use is made of a pumping device which is provided with an elastic diaphragm, is integrated in a water tank and, in a metered manner, feeds water to a liquid-channeling device, preferably comprising a sponge with an adjoining nozzle, where the water then ultimately comes into contact with a heating plate for evaporation purposes. In order to improve the transportation of water in the liquid-channeling device, a one-way valve may be arranged on the water tank.
DE-C-26 34 ""972 also discloses a hair-shaping appliance of the type described in the introduction. In the case of this hair-shaping appliance, the liquid-channeling device, preferably formed from a sponge and an adjoining tube, are inserted in a tubular housing. The tubular housing is arranged in a water tank, which can be filled with water and is likewise of tubular design, and, for the discharge of water, comprises two housing parts which can be displaced one inside the other counter to the force of a spring and, when displaced, serve for compressing the sponge and relieving the latter of loading. When the water tank is displaced counter to the force of a restoring spring supported on the drum, first of all the free end of the tube of the liquid-channeling device is brought into abutment against the heating device, until upon further displacement of the water tank, one housing part is displaced in the other housing part and compresses the sponge in the process. In this case, the sponge, for its part, discharges water, which then passes, via the liquid-channeling device, onto the surface of the heating device and evaporates there. The resulting steam passes outward into the free atmosphere via the through-passages formed on the drum.
Upon release of the evaporating device, the movable housing part is displaced away from the sponge again, on account of the pre-stressing of the spring, until its strike against an annular collar formed on the water tank. As stressing is relieved, air can penetrate into the chamber of the liquid container, via the equalizing bores formed on the sleeve, in order that no negative pressure forms in the chamber and no more water can thus flow out. The air taken in by suction flows around the outer surface of the sponge, on which the spring is centered, and thus passes into the chamber of the water tank.
In the case of this arrangement, it should be regarded as being less advantageous that if the evaporating device is actuated, for example, a number of times one after the other the heating device is fed more water than it can evaporate in the short period of time. Consequently, the evaporating device floods and excess water passes out at the through-passages. The result may be, on the one hand, that the hair is wetted too much but, on the other hand, also that the skin is burnt when the heated water passes out of the through-passages onto a user""s skin. It is also possible, when the hair-shaping appliance is not used for a relatively long period of time, for the water located in the liquid container to flow, via the liquid-channeling device, into the steam-distributor chamber and to be capable of flowing outward, via the through-passages, there without evaporating beforehand. This may result, for example, in corrosive damage to the hair-shaping appliance or also in an excess amount of steam and/or hot water passing out when the appliance is next used, as a result of which a user could sustain burns.
JP-A-11 46839, furthermore, discloses a gas-operated hair-shaping appliance in the case of which flame-free combustion of a gas takes place by means of a catalyst for heating up the heating tube. Provided in this case too is a steam-distributor chamber which is supplied with water by a liquid container. The liquid container is provided with an exchange valve, via which air flows in when water flows out of the liquid container. As has already been mentioned above, it is also possible here, when the appliance is not in use, for water to pass into the steam chamber via the liquid-channeling device and then to pass outward via the through-passages. On account of the fact that the through-passages, which are connected to the evaporating chamber, are arranged in the hair-shaping appliance separately from the outlets, which are connected to the combustion chamber, differing temperatures may occur at various locations of the drum, i.e. the temperature at the outlets is usually considerably higher than the temperature at the through-passages. A result of this is the non-uniform distribution of hot waste gases and steam on the circumference of the drum.
DE-A-27 27 665 discloses a steam-emitting hair-shaping appliance with a control arrangement for regulating the flow-medium discharge of the type described in the introduction. In the case of this hair-shaping appliance, which is preferably designed as steam curling tongs, there is formed between the outlet of the liquid container and the evaporating device a bimetallic plate, which changes under temperature and only opens the outlet of the liquid container when a predetermined temperature is reached, with the result that water can pass into the evaporating device and evaporate there. This ensures that steam can only be emitted from the hair-shaping appliance within certain temperature limits.
The invention features an electric or gas-operated hair-shaping appliance, in particular steam styling tongs.
The invention can prevent liquid from passing out of the drum even in the case of the dosing or pumping device being actuated a number of times in quick succession. This should also be the case when the hair-shaping appliance is not in use.
In the case of gas-operated hair-shaping appliances, the invention can prevent the ignition and combustion operations of the catalyst from being adversely affected by liquid. The invention can simplify the construction and the assembly of the hair-shaping appliance and to reduce the production costs.
In one aspect of the invention features an appliance for shaping the hair, comprising a forward and reverse stroke liquid dosing device, a tubular drum constructed to contact the hair, the tubular drum having through-passages and an evaporating device. The evaporating device comprises an evaporator chamber, a heating device and a steam distributor chamber. The evaporating device is constructed to produce steam from liquid delivered to the evaporator chamber and to deliver the steam through the through-passages in the tubular drum to treat the hair. During the return stroke of the dosing device, the appliance removes excess liquid from the evaporator chamber preventing excess water from collecting in the evaporating device and potentially spilling out on the consumer during use or storage. Even when the dosing device is actuated a number of times in quick succession, the evaporating device can be prevented from overflowing since during the return stroke of the dosing or pumping device, on account of the xe2x80x9cclosedxe2x80x9d liquid tank, excess water is sucked back into the water tank again via the liquid-channeling device. In addition, an undesirably high level of steam formation may be avoided by some aspects of the invention. Certain aspects of the invention can be used both for electrically operated and for gas-operated hair-shaping appliances.
In some implementations of the invention, the dosing device comprises, on the one hand, a pressure/suction pump operating on the displacement principle and, on the other hand, a liquid container, which can only be brought into connection with the atmosphere via its outlet. As a result, during the return stroke of the pressure/suction pump, excess liquid flows back into the liquid container via the liquid-channeling device. During the return stroke of the dosing or pumping device, the outlet also performs the function of an inlet for excess water which collects in the evaporator chamber or still adheres to the liquid-channeling device as an excess droplet.
Of course, it is also conceivable, instead of the liquid container provided, to integrate a further liquid container in the appliance, which is then provided with a separately working liquid-channeling device which channels excess water back into said second container.
Since excess liquid flows back immediately into the liquid container from the evaporating device, the hair-shaping appliance can be held as desired in a user""s hand without liquid passing out of the drum via the through-passages. This results in a particularly economical water-discharging device. That is to say, the liquid located in the liquid container is fully converted into steam without some of the water running out of the appliance unused.
In some implementations of the invention, the evaporating device comprises an evaporator surface which is located opposite the outlet, and in that the evaporator surface is part of an evaporator chamber which receives and discharges the liquid. This prevents the water which is discharged by the dosing device during the actuation will not escape even when the hair-shaping appliance is in the horizontal position. The chamber may form a relatively large evaporating surface and is constructed to retain small water droplets. It is possible here for the chamber to be of plate-like, cup-like or pot-like design.
In some implementations of the invention, the liquid-channeling device comprises a wick which is fastened in the outlet and of which the free, delivering end terminates a small distance in front of the evaporator surface when liquid is discharged or received. This can reduce exposure of the wick to an excessively high temperature. This increases the service life of the wick. Moreover, the wicks need not be pressed against the evaporating surface in order for water to be discharged in a metered manner. It is also possible, however, upon actuation, for the wick to come into contact with the evaporator plate and to be pressed against it slightly in the process.
In some other implementations of the invention, the wick can transport both water and air in both directions of flow. This arrangement allows for a straightforward metering of the liquid.
In some other implementations of the invention, the end of the wick opposite the evaporator chamber projects into the liquid container. This provides a relatively large receiving surface for the liquid on the wick, and allows for a liquid to be drawn from the liquid container even when the liquid container is in the horizontal position or is almost empty.
In other implementations of the invention, the wick is spaced from the evaporating surface a sufficiently small distance so that, during actuation of the dosing device, a droplet of water protruding off a surface of the wick can come into contact with the evaporating surface and for parts of the droplet to flow out, these then evaporating on the hot evaporator-chamber surface.
In yet other implementations of the invention, the dosing device and the chamber of the liquid container form a piston/cylinder arrangement, with the dosing device representing the cylinder and the chamber representing the piston. This allows for a particularly straightforward integration of the dosing device with the liquid container. This allows for delivery of a relatively large or small amount of liquid, depending upon piston stroke length. In this case, the piston has to be displaced into its starting position again, by means of a spring, in order for the automatic suction stroke to be executed.
In other implementations of the invention, the dosing device comprises an elastically deformable wall which forms part of the liquid container. The elastically deformable wall can easily be actuated for discharging liquid. In addition, the wall moves back automatically to its original shape again because of its elastic expandability, allowing for the suction stroke to be executed without a user""s intervention. The elastically deformable wall may be fastened on the liquid container, for example, by injection molding, screw connection, adhesive bonding or in some other manner, but it may also be designed as an integral molding with the liquid container. In this case, the wall thicknesses should be coordinated with one another such that, upon actuation of the deformable wall, the liquid container itself hardly deforms.
It is advantageous for the deformable wall to be outwardly curved so that the dosing device can discharge considerable quantities of liquid. The elastically deformable material and the wall thickness of the deformable wall have to be selected such that the wall can be easily moved by hand and the wall produces a sufficient suction-stroke action in the chamber of the liquid container so that excess water which may be present in the evaporating chamber or on the wick can be sucked back into the liquid container sufficiently quickly via the liquid-channeling device.
In still other implementations of the invention, the liquid container can be displaced in the axial longitudinal direction of the hair-shaping appliance in an insulating sleeve fastened in the drum, counter to the force of a compression spring. The outlet, with its liquid-channeling device is formed at the end of the liquid container which is located opposite the evaporator surface, and the deformable wall is formed at the other, remote end of the liquid container. Marked deformation of the elastically deformable wall happens when the liquid container, once displaced, moves against a stop. This ensures that water only flows into the evaporating chamber when the liquid-channeling device butts against the base of the evaporating chamber or, better, terminates a short distance in front of said chamber. The rigidity of the elastically deformable wall is thus selected to be high enough for the liquid container, initially without any marked elastic deformation of the wall, to be displaced counter to the force of the compression spring until the wick has reached its liquid-discharging position in the evaporating chamber. This ensures that excess liquid will be channeled back into the liquid container via the wick. For easy displacement of the liquid container, the latter is fastened in a non-displaceable manner in the drum in an insulating sleeve, which is fastened in a stationary manner in the drum. The insulating sleeve protects the liquid container, which is preferably plastic, from thermal overloading.
In other implementations, the deformable wall is replaceable. The replaceable wall may be connected to the liquid container by means of a thread, a clip device or by any other means.
In still other implementations, at least one stub or radially extending protrusion projects on the outer surface of the liquid container and, following the insertion of the liquid container, the stub engages in a bayonet-like manner behind a recess formed on the insulating sleeve. The recess is adjoined by a gap which runs in the longitudinal direction of the insulating sleeve and allows further displacement of the liquid container in the direction of the evaporator surface. This allows the liquid container to be easily removed from the hair-shaping appliance in order to be filled with a liquid, preferably water or water enriched with fragrances, hair-treating substances or other materials. Locking takes place when at least one stub projecting radially on the liquid container initially engages in a recess, when inserted, and is then secured by rotation, but can be moved back and forth within certain limits in the longitudinal direction of the liquid container by means of a further recess adjoining the first recess. Instead of one stub, of course, it is also possible for two or more stubs to be formed on the circumference of the liquid container. In this situation, it is also necessary to introduce into the sleeve a corresponding number of recesses, which then cooperate with the respectively associated stub. This improves the guidance of the liquid container.
In other implementations, the base of the liquid container is formed by a sleeve with an outlet and connected to the outlet and projecting out of the sleeve is the liquid-channeling device. The sleeve is fastened releasably on a tube of the liquid container by means of a second releasable connection, preferably a bayonet closure or thread connection. This ensures that only when the liquid container has been removed from the hair-shaping appliance that it can be filled with water, once the closure cap has been opened. The operation of removing the liquid container from the hair-shaping appliance, which is necessary for filling the liquid container, can avoid malfunctioning of, and thus possible damage to, the hair-shaping appliance, because a user is never tempted to hold the entire appliance under a water source during the filling operation. The forced separation of the liquid container from the hair-shaping appliance facilitates handling of the filling operation since, in this case, the hair-shaping appliance can be set to one side and the liquid container can be held more easily under a faucet or a container.
In still other implementations, on the outer wall of the sleeve is formed a stop on which the compression spring is supported on one side, and formed on the inner wall of the insulating sleeve is a base on which the other side of the compression spring is supported. This allows for following actuation, the water tank is automatically moved back into its starting position again by the force of the compression spring as soon as the actuating force applied to the elastic wall by a user decreases.
In still other implementations, mounted on the external diameter of the compression spring is a sealing ring, of which one end butts with sealing action against an end surface of the sleeve and the other end butts with sealing and sliding action against the inner wall of the insulating sleeve. This allows for the compression spring, in addition to serving as a restoring spring for the liquid container, also performs the retaining and sealing function of the sealing ring which butts with sealing action against the liquid container and seals the evaporator chamber in relation to the bore formed in the insulating sleeve and also in relation to the liquid container. The sealing ring here butts with sliding action in the bore of the insulating sleeve, to seal the evaporator chamber when the liquid container is displaced.
In the case of a hair-shaping appliance that heats by using flame combustion of a gas by means of a catalyst, the insulating sleeve can be introduced into the drum to such an extent that a steam-permeable ring, preferably a felt element, is clamped in between the free end of the insulating sleeve and the side end of an evaporator chamber formed by the evaporator plate, so that the steam produced in the evaporator chamber can only pass into the steam-distributor chamber via the steam-permeable ring. This allows for a particularly straightforward arrangement of the catalyst and the steam-distributor chamber being formed in a common chamber. The evaporating chamber no longer needs to be hermetically sealed in relation to the combustion chamber. This allows for better mixing of the steam and the combustion gases and thus can heat up more uniformly. This may allow a more uniformly hot jet of steam to pass out at the through-passages formed in the drum. In addition, the drum is also heated up better and more uniformly in this way.
Allowing water droplets to pass onto the catalyst, can cause considerable ignition problems since a comparatively large amount of ignition energy would have to be applied in order for the water located on the catalyst to evaporate and to ignite said catalyst for the flame-free combustion process. A single chamber simplifies the construction of the hair-shaping appliance to a considerable extent and, in addition to the abovementioned advantages, may reduce the production costs.